Is Astrophotography Without Tracking Possible? (2022)
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Is Astrophotography Without Tracking Possible? (2022)
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Re: Is Astrophotography Without Tracking Possible? (2022)
#2Tracking is needed for when you want to do say 15 second exposures.
The new technique for astrophotography isnt long exposures. Its about fast exposures in an attempt to maximize good atmospheric wobble.
Re: Is Astrophotography Without Tracking Possible? (2022)
#3Tracking is needed for when you want to do say 15 second exposures. The new technique for astrophotography isnt long exposures. Its about fast exposures in an attempt to maximize good atmospheric wobble.
That's called lucky imaging, yes. It's not particcularly new btw. Also, for capturing very faint deep sky objects like galaxies and nebulae you need long exposures of several minutes to get the deeper detail.
Re: Is Astrophotography Without Tracking Possible? (2022)
#4Yes, and it is already happening in professional astronomy. For example, the "Antarctic Tianmu Plan" [0] have shown that you can successfully capture non-trailed images without using tracking mounts by using drift-scanning CCDs—basically letting the sky move across your sensor while the detector is read out at the same rate.
Re: Is Astrophotography Without Tracking Possible? (2022)
#5Yes, and it is already happening in professional astronomy. For example, the "Antarctic Tianmu Plan" [0] have shown that you can successfully capture non-trailed images without using tracking mounts by using drift-scanning CCDs—basically letting the sky move across your sensor while the detector is read out at the same rate. [0] - https://doi.org/10.1117/12.3019468
You can, but dark noise is a problem with this technique as your SNR per bucket ends up being low. The purpose of long exposures with tracking is to maximise your SNR.
Also, it helps significantly to be in Antarctica, where the relative movement is much slower than it is at lower latitudes — and to have multiple telescopes - and low noise CCDs, in a cold, dry environment.
Sadly, most of us don’t have those luxuries.
Re: Is Astrophotography Without Tracking Possible? (2022)
#6Yes, and it is already happening in professional astronomy. For example, the "Antarctic Tianmu Plan" [0] have shown that you can successfully capture non-trailed images without using tracking mounts by using drift-scanning CCDs—basically letting the sky move across your sensor while the detector is read out at the same rate. [0] - https://doi.org/10.1117/12.3019468
You can , but dark noise is a problem with this technique as your SNR per bucket ends up being low. The purpose of long exposures with tracking is to maximise your SNR. Also, it helps significantly to be in Antarctica, where the relative movement is much slower than it is at lower latitudes — and to have multiple telescopes - and low noise CCDs, in a cold, dry environment. Sadly, most of us don’t have those luxuries.
what about computational methods? i have always wondered how stacking many short exposures without tracking compares to deconvolution of a single long exposure. it seems that there is software able to do this by taking into account both motion blur and the PSF of the imaging system:
https://siril.readthedocs.io/en/stable/processing/deconvolut...
Re: Is Astrophotography Without Tracking Possible? (2022)
#7Nowadays, most people who say astrophotography don't mean Deep Sky photography, hunting planets, nebula and galaxies. It's mostly the sky over a wide-angle landscape. "Astrophotography" happens at Totally viable untracked. The classic 14mm prime has gone from f2.8 to f1.8 to f1.4, and sensors have become really good at high sensitivity for a 15 second exposure. Quite often, that's enough.
The hairy part is when it's not quite enough, and exposures have to be stacked. I have a crop sensor camera (canon 1.6x, so 40% area) with an f/2 lens that I like to step down further, and a good Starscape this way will take 10-40 exposures. I can stack those no problem, but it's trees on the horizon that are problematic. The ground stack and the sky stack have to clash, and a complex shaped border will always look photoshopped, because it is.
Old school Deep Sky is losing its appeal due to a) pictures being available online, meaning that you've already seen the better version of the same photo, and b) the images being sterile and without context, with no relation to the photographer's story. Milky Way in a national park says "I've been there!" in a way that a shot of the Whirlpool Galaxy just can't.
Re: Is Astrophotography Without Tracking Possible? (2022)
#8Earlier quoted context omitted.
You can , but dark noise is a problem with this technique as your SNR per bucket ends up being low. The purpose of long exposures with tracking is to maximise your SNR. Also, it helps significantly to be in Antarctica, where the relative movement is much slower than it is at lower latitudes — and to have multiple telescopes - and low noise CCDs, in a cold, dry environment. Sadly, most of us don’t have those luxuries.
what about computational methods? i have always wondered how stacking many short exposures without tracking compares to deconvolution of a single long exposure. it seems that there is software able to do this by taking into account both motion blur and the PSF of the imaging system: https://siril.readthedocs.io/en/stable/processing/deconvolut...
The problem is that the noise can swamp the signal. Another example of this would be doing astrophotography during the day. The sun doesn't block anything, it just makes the sky glow with "noise". Theoretically it has exactly as much signal from space as it does at night, but because the sun adds so much noise it's completely lost.
Re: Is Astrophotography Without Tracking Possible? (2022)
#9Isn't trackerless astrophotography one of the main use cases for software that can do stacking like Siril [0] and similar tools [1] out there?
1. https://www.reddit.com/r/AskAstrophotography/comments/1b7fz3...
Re: Is Astrophotography Without Tracking Possible? (2022)
#10Isn't trackerless astrophotography one of the main use cases for software that can do stacking like Siril [0] and similar tools [1] out there? 0. https://siril.org/ 1. https://www.reddit.com/r/AskAstrophotography/comments/1b7fz3...
Siril is for integrating a lot of images together that are tracked and then removing the background. While you may be able to use it untracked it is primarily for tracked images.